This invention relates to exercise apparatus for supportively aiding a patient's therapeutic upper limb movements, and more particularly to apparatus of that type equipped with reliable and easily adjustable means for varying the limits of a patient's muscle movements.
Rehabilitation of the function of a patient's upper limbs after an injury will almost always include apparatus-aided therapeutic exercise for the abduction and adduction of the patient's upper limbs and shoulders (e.g., those muscles of the upper body that effect generally lateral movement of the arms away from and toward the vertical axis of the body). Imposing special limits on the permissible extent or range of the patient's abductive and adductive limb movements during the rehabilitation process generally is advisable so as to prevent further injury or to promote strengthening of targeted muscles. These limits and others determined to be desirable by a therapist may be maintained the same over a period of time or may be gradually expanded or contracted (to allow a greater or lesser range of limb movement), with or without varying the resistance/assistance to movement, as the patient heals and strength returns.
Apparatus of this general type has typically employed a boom situated above each of the patient's upper limbs. A dependent line (and attached arm or hand sling) is suspended from each boom to provide support for the limb below. Known apparatus having means for setting limits to the range of assisted or supported lateral arm movements has permitted infinitesimal variation of the limit settings but at sacrifice of the ease and speed of adjustment. Reliance on friction to hold the relationship between parts governing the limit settings for lateral arm movement has its uses, but it requires a rotary tightening step that takes time. Also, friction held settings are not quickly and easily and reliably duplicated (or reliably varied) from day to day. This problem is encountered by therapists serving multiple patients in a large institution. Quick adjustability would be desirable.